The present invention relates to an image reading device for a copier, facsimile apparatus, printer or similar image forming apparatus and, more particularly, to an image reading device having two document setting sections and capable of reading documents laid on both of the two setting sections.
Japanese Patent Laid-Open Publication No. 60-33550, for example, discloses an image reading device for a copier and having a single reading section and two document setting sections sharing the reading section. When the device taught in this document is operated in a so-called interrupt copy mode, unoccupied one of the two document setting sections is used. Specifically, assume that a person desires to effect interrupt copying when the copier is reproducing a plurality of documents with an ADF (Automatic Document Feeder). Then, the person simply inserts desired documents one by one into an exclusive inlet independent of an ordinary document tray without regard to the paper transport timing or the copy timing of the copier body.
The above prior art image reading device achieves the expected effect so long as documents in the form of cut sheets are dealt with. However, when a person desires to copy, e.g., a book document, the person must open the ADF after carefully confirming the interruption of paper transport in the ADF because a single glass platen is shared by both the documents of the ADF and the book document. Careless handling of the ADF would result in critical troubles including the discontinuous pages of copies produced with the ADF. This increases the operator's burden and thereby causes the operator to sidestep the interrupt copying itself.
To meet the need for a space-saving configuration, a current trend in the imaging art is toward an ADF having a document setting or feeding section and a document discharging section which are stacked one upon the other in a reading section so as not to exceed the size of a glass platen. In this case, a book document or similar interrupt document cannot be copied unless all the documents are removed from the above sections of the ADF, and then the ADF is opened. This renders the interrupt copying function impractical.